The field of communication has witnessed a great revolution over the past two decades. In particular, there has been remarkable growth in wireless communications, ranging from cellular communication to wireless local area networks. This growth has been propelled by the continuous exponential advances in computing hardware, popularly referred to as the Moore's “law”, which has enabled integrated circuit implementation of sophisticated digital signal processing (DSP) algorithms. Future communication system designs are expected to continue riding the Moore's law to build low-cost low-power DSP-centric transmitter/receiver (transceiver) architectures.
Next generation wireless communication systems target data rates that are orders of magnitude (tens of Gbits/sec) larger than those offered by current systems. One way to achieve these high data rates is to scale up the system bandwidth, for example, using the wide swaths of spectrum available in the millimeter (mm) wave band. While offering the potential to provide drastically increased data rates, the design of such high bandwidth systems imposes several challenges. A particular one is the bottleneck imposed by the ADC technology: high-speed high-precision ADCs are either not available, or are prohibitively costly and power hungry. Recent state-of-the-art surveys indicate, for instance, that ADCs that can sample at rates in Gigasample/s, with a (relatively modest) precision of 6-8 bits, have power consumption of the order of several hundred milliwatts. This potentially makes the ADC one of the most dominant power consumption modules in the entire receiver processing chain.
Given the preceding constraints imposed by evolution of the ADC technology, it is important to consider communication system and algorithm design towards alleviating the ADC bottleneck. This can be achieved by considering the use of low-precision ADCs (e.g., 1-4 bits). This drastic reduction of the ADC precision, however, significantly impacts the performance of the communication link. In particular, use of existing principles and designs for communication systems, in conjunction with low-precision ADC, results in severe performance degradation. Consequently, it is important to consider novel design principles for reliable communication system performance with low-precision ADC.